Wrentit: stable
Wrentits remain relatively common at Palomarin, despite long-term habitat change and climate change.
Song Sparrow: declining
Song Sparrows were once one of the most common species at Palomarin, but their numbers have declined locally, thought to be a result of the long-term habitat change.
Nuttall's White-crowned Sparrow: declining
Nuttall's White-crowned Sparrows have declined dramatically as the local vegetation has shifted from open scrub and grassland to dense coastal scrub and Douglas fir forest.
Spotted Towhee: stable
Spotted Towhee populations remain relatively stable at Palomarin.
California Scrub-Jay: stable
California Scrub-Jays are infrequently caught in our mist-nets, in part because they are larger than most of the species we catch and are more easily able to get themselves out! Capture rates are low but steady.
Wilson's Warbler: mixed
Wilson's Warbler numbers have declined slightly in our forested mist-netting area, even though the number of nesting territories has increased in other parts of our study area.
Swainson's Thrush: mixed
Swainson's Thrush numbers have remained steady in our forested mist-netting area, even though the number of nesting territories has increased in other parts of our study area.
Fox Sparrow: stable
Fox Sparrows are relatively steady, except for an unusual spike in their numbers in 2013, possibly the result of an extremely productive nesting season in Alaska.
Golden-crowned Sparrow: declining
Golden-crowned Sparrows have been slowly declining, but with a bump in their numbers in 2013 similar to Fox Sparrow, possibly the result of an extremely productive nesting season in Alaska.
Hermit Thrush: declining
Hermit Thrushes have declined slightly over the years.
Year-Round Residents
Present at Palo all year, these bird species often maintain their territories even during the nonbreeding season. Changes in the capture rates of these species are most likely to reflect changes to the local habitat and climate. While most of these populations are relatively stable, we have seen declines in Nuttall’s White-crowned Sparrows and Song Sparrows, thought to be related to the local habitat changes.
Seasonal Migrants
Present at Palomarin only for part of the year, Neotropical migrants spend the spring and summer breeding season with us, then migrate to the tropics of Latin America to spend their winter. Changes in the capture rates of these species may reflect a combination of changes in habitat or climate in the tropics, along their migration routes, or local effects of changes at Palomarin.
For both of these species, trends in capture rates (from our forested mist-netting area) tell a different story than the growing number of nesting territories throughout other parts of the Palomarin study area, which are undergoing rapid habitat change.
Neotemperate migrants spend the summer as far north as Alaska, and then migrate to spend the winter with us. Changes in the capture rates of these species may reflect changes in habitat or climate in Alaska or Canada, along their migration routes, or local effects of changes at Palomarin.
